
where \(\phi _{1} \equiv \hat{\phi }(0)\)  and \(\phi _{2} \equiv \hat{\phi }(\pi )\) . Ref. [1]} introduces a convenient \(W[\hat{\phi }]\)  with the following specific form:Here \(u\)  is a parameter, and not the \(\hat{u}\)  field of Eq. REF .
\(W[\hat{\phi }(\varphi )] = 12 kr_{c} - \dfrac{1}{2}\hat{\phi }(\varphi )^{2}\,ur_c~.\) 
